Oil heating appliance



Aug. 10, 1965 H. BAUMANNS ETAL OIL HEATING APPLIANCE 2 Sheets-Sheet 1Filed July 3, 1962 IN VE N TOPS H Bamnenn: 4 F 5052221252 i +ww Aug. 10,1965 H. BAUMANNS ETAL OIL HEATING APPLIANCE 2 Sheets-Sheet 2 Filed July3, 1962 /N VE N TOPS H. 54 uMAm/s 9 F cAW/rz United States Patent M3,199,558 011. IEATENG APPLEANtIlE Herbert Baumanns, 187 Beil rstrx, andFriedrich Schmitz, 54 Giesenldrchenerstn, both of Rheydt, Germany Filedluiy 3, 1%2, Ser. No. 207,255

Claims priority, application Germany, July 5, 1961,

B 63,148 Claims. (Cl. 158--71) The invention relates to an oil heatingappliance with a burner having a burner plate or the like and at leastone oil supply conduit leading to the burner.

Oil heating appliances are intrinsically known. They usually possess anoil tank from which oil is supplied by means of a supply line to aperforated burner plate where it is ignited. The burner housing may beperforated, so that the air for combustion is induced to flow in fromthere. Alternatively a fan supplies air to the burner plate. However,the use of fans is expensive, and they also produce an undesirably highnoise level, and in addition an electrical connecting cable must beprovided for them. Moreover, the fan and cable, etc., must be wellshielded from heat from the burner housing and from the hot air. Such anarrangement is expensive and its operational reliability is imperfect.The principal disadvantage of the conventional oil heating appliances orof the oil burners, however, lies in the fact that they do not operatewith sulhciently high efiiciency, since the mixing of oil, oil vapourand air for combustion is not performed sufficiently thoroughly.

To obviate the aforesaid disadvantages, according to the invention anoil heating appliance comprises a burner having a burner plate or thelike and at least one oil supply conduit leading to the burner,oil-pressurizing means connected to one end of said supply conduit andat least one oil vapour outlet means at the burner end of said supplyconduit whereby fuel oil vapour in said conduit is maintained underpressure and a jet of oil vapour is blown or sprayed at said outletmeans into an intake pipe connection leading to the burner plate.

By this means, the thermal efiiciency of the heating appliance issubstantially enhanced, since not only is oil supplied under pressure,but the jet of compressed oil vapour which emerges sucks in andvigorously whirls and mixes with an increased volume of air forcombustion which is burned at the burner plate or the like withgeneration of a greater quantity of heat, or else, for a smallerconsumption of oil, a quantity of heat is liberated which corresponds tothe conventional oil heating appliances of equivalent type. Therefore,an increase in efiiciency or an increase of temperature may be achievedselectively. Above all, more complete and soot-free combustion isachieved according to the invention.

In further elaboration of the invention, it is proposed that a nozzle ora Venturi tube whose outlet cross-section is many times smaller thanthat of the intake pipe connection be used, and that the cross-sectionof the intake pipe connection is reduced in the region of the nozzleoutput aperture. By this means, the arrangement according to theinvention is improved inasmuch as the jet of oil vapour entrains the airfor combustion more strongly and a greater quantity of air is induced toflow into the intake pipe connection. It is further proposed that atleast one pressure oil tank or at least one pressure oil pump be used togenerate the compressed fuel oil vapour. It is therefore possible toachieve a better heating effect by relatively simple means. Anapertured, slotted or perforated burner plate is used, while the nozzleor nozzles out of which a jet of oil vapour is blown are arranged at adistance from the burner plate, so that combustion takes place at thelatter at normal pressure.

The invention may be specifically varied by the use 3,1995% FatenteclAug. 10, 1965 of a heat exchanger heated by the waste heating gasesand/or by the radiation of the heating appliance, and through which orat which the combustion .air condmt and/or the fuel oil vapour conduitis passed, so that the said conduit is or the said conduits arepreheated. As compared with the supply of oil or of air for combustion,this additionally achieved either an increase in temperature and/ or anincrease in efficiency.

The invention will be further explained with reference to theaccompanying drawings, which illustrate diagrammatically exemplaryconstructions, and in which: I

FIG. 1 shows a side elevation of an oil heating appliance in accordancewith the invention, FIG. 2 is a similar view of a modified constructionand F16 3 is a front elevational view of the burner plate of FIG. 1.

Referring to FIG. 1, an oil-pressurizing means 10 is indicateddiagrammatically. This means may be a gear pump or the like, and it isalso possible to use a static pressure device, e.g., at least onepressure oil tank. A column of oil is forced up by the means 16 andpasses first into the lower part of an oil supply conduit 11 so that anoil level, designated 12, developes in the latter. Obviously, the saidoil level may also be substantially higher in the conduit. In the oilsupply conduit the fuel oil is present as vapour above the level 12; ifit is desired to obtain a greater volume of vapour and also to achieve ahigher oil vapour temperature, the conduit 11 may be heated at one or aplurality of points. The oil supply conduit 11 leads into outlet means14, which may be a nozzle or the like, whose outlet cross-section is sodimensioned that a relatively sharp jet of oil vapour, or a number ofvapour jets, is blown or sprayed out and the oil vapour presure in theconduit 11 is maintained roughly constant. The nozzle 14 therefore worksfirstly as a throttle device to prevent excessively rapid discharge ofthe oil vapour, and also to prevent a drop in the pressure in theconduit 11;

The jets of oil vapour leaving the nozzle 14 in the direction of thearrow are delivered to an intake pipe connection 15, whose cross-sectionis constricted at 15 so that strong entrainment of the requisite air forcombustion is achieved. In many cases it is convenient to place theoutlet aperture of the nozzle 14 roughly in the centre of theconstriction 15. The mixture of oil vapour and of air for combustionpasses via the intake pipe connection 16 to a burner plate 18 or thelike, which is provided with a large number of slots, apertures,perforations or the like. Ignition takes place at the burner plate bymeans of a device, which may be for example an electrical incandescentspiral 19, and combustion takes place in a housing (not shown) in frontof the burner plate 18, roughly at atmospheric pressure. The burnerplate 18 may be a ceramic plate.

According to FIG. 2, the arrangement described may be varied so that atleast one outlet nozzle 14a is located so that the oil vapour jet isblown in more directly in the direction of the burner plate. The upperpart of the oil vapour supply conduit is designated 13a; this conduitmay be taken behind the rear of the burner plate. As a rule, the vapourjet is then divided at the rear and is whirled in a chamber 17 of theoil heating appliance together with air for combustion which is drawnin.

It is further possible to produce an appliance which is provided with aheat exchanger 29 (see FIG. 1). The hot waste gases of combustion, forexample, may be supplied to the said heat exchanger via a heatingconduit 21. The heating conduit 21 may be disposed as a heating coilwhich surrounds the upper part 13of the supply conduit for the fuel oilvapour, so that the oil vapour and the conduit 13 are heated. Higherefiiciency of the combustion medium is thereby achieved since a smallerquantity of heat has to be withdrawn-e.g., from the burner plate 18-inorder to heat the oil to be burned to fiame temperature. Or in otherwords, a higher heating temperature is achieved. However, heating of theconduit 13 may also be performed differently. It may be etfected bypassing the conduit 13 itself through the heat exchanger 20. The heatexchanger 20 may likewise serve for preheating the air for combustion bypassing an air intake conduit through the heat exchanger 20. The saidair intake conduit passes through as far as the nozzle 14, or the latteris introduced into the air intake conduit. The arrangement may also bethat both the air intake conduit and the oil vapour conduit 13am passedthrough the heat exchanger 20. Preheating of the air for combustion alsoserves to achieve greater efiiciency, and the heatable surfaces are thensubject additionally to an increase in temperature by the same quantityof heat which would have been necessary to warm the combustion air inother circumstances. Moreover, the waste gases may be used to heat thehousing, a housing cover of the burner plate or the like, or may also bedelivered directly to a flue pipe 22.

While it is true that it is not essential for complete efiiciency tocompletely fill the conduit 11, it is sufficient that vapourized oilleaves the nozzle 14. Of course, it is desirable to start heating theconduit 13 as soon as possible in order to obtain the desired and/ orsulficient vapourization. However, it should be apparent that one canobtain suthcient vapourization when the conduit 21 of the heat exchanger20 is the sole heat source and the portion 13 of the conduit is notpositioned in front of the burner plate. When the burner plate andconduit are in diiferent planes, the coils of conduit 21 can beincreased and extended into the vertical portion 13 or 13a of theconduit 11 and, if desired, to and beyond the level 12.

The appliance according to the invention is especially suited as aninfra-red heating appliance. Such infra-red burners operate at a lowtemperature such that the maximum radiation takes place at thewavelength of infra-red waves, about 7600 A. and above. Now, the wasteheating gases in particular have a low temperature, which may be forexample only a few hundred degrees, so that the quantity of heat whichthey contain tends to lower the temperature only slightly for the burnerplate or the like of the infra-red burner, which is likewise relativelylow. In other words, the quantity of heat delivered by the heating gasesis still great enough, particularly in the case of infra-red burners,for the quantity of heat at the burner plate or the like to beconsiderably increased, which is equivalent to higher efiiciency or tothe delivery of a higher heating capacity to the exterior.

The invention may further be embodied to use the quantity of heat in thewaste heating gases either to initiate or to enhance the vaporisation ofthe liquid fuel oil. The arrangement may be made so that a heating coilfed by the waste heating gases is wound about the conduit for the liquidfuel oil and/ or about the conduit for the vaporised fuel. Thevaporisation may further be initiated or enhanced by heat radiated bythe burner itself, and finally, waste gas heating and heating byradiation may be used jointly to produce vaporisation. Furthermore, itmay be convenient to use an axiliary appliance, e.g., an electricalauxiliary heating appliance, which efects prevaporisation before thefuel in the form of vapour is ignited. The reliability of ignition isthereby enhanced, or the commencement of ignition is accelerated.

What is claimed is:

1. An oil-burning heating appliance comprising a burner plate at whichthe oil is burned in air, an oil supplyconduit, oil pressurizing meansconnected to one end 4 of said supply conduit and adapted to supply oilthereto under pressure, an oil vapor outlet means connected to the otherend of said supply conduit, an intake pipe connection leading from saidvapor outlet means to said burner plate, the outlet means being a nozzlethe outlet cross-section of which is many time smaller than that of theintake pipe connection, the cross-section of the intake pipe connectionbeing reduced in the region of the nozzle outlet aperture whereby fueloil vapor in said conduit is maintained under pressure and a jet of oilvapor is blown through said nozzle into the intake pipe, said intakepipe being open to the atmosphere so that the jet of oil vapor draws airinto the intake pipe for mixing with the oil vapor, a heat exchangerheated by the waste heating gases resulting from the combustion of saidoil vapor and air, said heat exchanger comprising a waste gas tubesurrounding at least a portion of said intake pipe at a point where theair for combustion passes therethrough, and an exhaust gas intake memberconnected to said waste gas tube at one and thereof and positionedadjacent said burner plate, the other end of said exhaust gas tube beingconnected to the normal exhaust gas facilities for the appliance, saidexhaust gases passing through said waste gas tube so that said conduitis heated.

2. The appliance according to claim 1, in which vaporisation of theliquid fuel is effected by radiated heat in addition to heat in thewaste gases.

3. The appliance according to claim 1 in which the burner plate is aninfra-red burner.

4. The appliance according to claim 2 in which the burner plate is aninfra-red burner.

5. An oil-burning heating heating appliance comprising -a burner plateat which the oil is burned in air, an oil supply conduit, oilpressurizing means connected to one end of said supply conduit andadapted to supply oil thereto under pressure, an oil vapor outlet meansconnected to the other end of said supply conduit, an air intake pipeconnection leading from said vapor outlet means to said burner plate,said burner plate being an infra-red burner, a heat exchanger forpreheating combustion air supplied to said burner, and a conduit fordirecting heat from said burner to said heat exchanger.

References Cited by the Examiner UNITED STATES PATENTS 338,907 3/86Acheson -56 X 458,390 8/91 Gearing 158-5 1,122,936 12/14 Jackson 158-711,324,863 12/19 Watkins 158-71 1,386,608 8/21 Du Pont 158-36 1,602,30210/26 Evans 158-71 X 1,689,667 10/28 Free 158-36 1,849,236 3/32 Killam158-108 2,775,292 12/56 Van Der Lee 158-62 2,812,017 11/57 Vant 158-812,902,086 9/59 Hobson l58-36.3 2,992,469 1/60 Rowe 158-36 3,084,736 4/63Mentel et al 158-114 FOREIGN PATENTS I 27,040 12/ 23 France. 1,070,3172/54 France.

821,463 10/59 Great Britain.

JAMES \V. \VESTHAVEN, Primary Examiner.

FREDERICK L. MATTESON, 1a., PERCY L.

PATRICK, ROBERT A. DUA, Examiners.

5. AN OIL-BURNING HEATING HEATING APPLIANCE COMPRISING A BURNER PLATE ATWHICH THE OIL IS BURNED IN AIR, AN OIL SUPPLY CONDUIT, OIL PRESSURIZINGMEANS CONNECTED TO ONE END OF SAID SUPPLY CONDUIT AND ADAPTED TO SUPPLYOIL THERETO UNDER PRESSURE, AN OIL VAPOE OUTLET MEANS CONNECTED TO THEOTHER END OF SAID SUPPLY CONDUIT, AN AIR INTAKE PIPE CONNECTION LEADINGFROM SAID VAPOR OUTLET MEANS TO SAID BURNER PLATE, SAID BURNER PLATEBEING AN INFRA-RED BURNER, A HEAT EXCHANGER FOR PREHEATING COMBUSTIONAIR SUP-